Speed ratio

Get advice on which kayak may be best for you. Compare the different models. "VS."

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diemonde
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Speed ratio

Post by diemonde » Mon Aug 02, 2010 12:18 am

The Expedition is faster then the Frame, the Fusion is faster then the Expedition. But how much is the difference. I was just wondering what the speed ratio between the several types is. So people who have own multiple AE kayaks, please enlighten me ;-)

diemonde
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Joined: Tue Aug 04, 2009 12:46 am
Location: The Netherlands, Europe

Post by diemonde » Thu Aug 05, 2010 11:43 pm

Well I did some investigation and found:
http://www.midwestik.com/midwestik/midw ... /speed.htm

This let's you calculate the max hull speed using width and length.

AE Frame: 2.38 Mph
AE Expedition: 3.99 Mph

AE Convertible: 4.86 Mph

AE AirFusion: 5.42 Mph

The calculations are not exact because there are things like hull speed etc. and I know the AE Frame can go faster than 2.38 Mph.

paulrb02
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Post by paulrb02 » Fri Aug 06, 2010 8:30 am

Yeah according to my Garmin GPS my best speed has been 5.6 mph in my expedition, and I was on a lake.

But its cool to see calculations like that, thanx for the link.

JCOOLEY
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Post by JCOOLEY » Sat Aug 07, 2010 7:51 am

Don't forget that if you throw in a backbone this will increase the speed as well. I know that most paddlers get the Fusion faster than that as well. Easily over 6.

Jeremy

lee johnson
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1.55 X Sq. Rt. of Length of Waterline

Post by lee johnson » Mon Jan 17, 2011 10:42 am

In a recent paddling.net posting, Cliff Jacobsen, in comparing the virtues of canoes vs. kayaks, says a good formula for computing the speed of a watercraft is to take the square root of the waterline, measured in feet, and multiply by 1.55. Here are some results:

Lagoon (8'4"): 4.5 mph
AF 1 (10'5"): 5 mph
Expedition (13'): 5.6 mph
Convertible (15'):6 mph

and so on.

Cliff Jacobsen makes the additional point that even though a 15' kayak and a 15' canoe may yield the same result for a top speed, the kayak may be easier to paddle: less effort because less displacement. To this very sensible point, I would add two more:

1) Hull Shape: a flat hull will be less efficient than a V-shaped hull. More effort usually will be required to maintain a given pace with a flat hull because of the way back-drag develops. Here is a secret of AE's BackBone, which imparts a V-shape to the original flat hull and even gives a hint of a reverse soft chine (gull wing) from the hull to the sides.

2) Paddle Shape: the narrower the blade of the paddle, the faster the beat to move that water. Some of the newer paddles have large, stiff blades in asymmetrical dihedral designs; and this, plus an excellent "swing weight" (ratio of weight of blades to weight of shaft) can improve top speeds and the ease of maintaining them.

This having been said, I can personally attest that the 10'5" Advanced Frame kayak is, with BackBone, much faster than the 8'4" Lagoon and its flat hull: much faster than the formula above suggests. The ease of maintaining a given speed also becomes easier the longer and narrower a kayak is; but some of us like the benefits of exercise that our Lagoons give us (not to speak of ease of use, stability, and terrific maneuverability).

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PJohanson
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Post by PJohanson » Tue Jan 18, 2011 10:25 pm

Jeremy's right that adding a backbone makes for a faster boat. And I think Lee's got it right, both in the formulas for calculating speed and for acknowledging that speed aint the only thing to think about when choosing a kayak model.
But top possible speed for a kayak is affected by the paddler as well. A very large-shouldered man may be frustrated when trying to go at top speed in either the Lagoon or AdvancedFrame 10.5, if he finds it hard to use a short stroke and quick cadence. I've noticed as a smaller person that I can keep up a better pace in my Dragonfly (an older version of the Lagoon) than my friends can. I'm used to short strokes and a quick cadence.
I find the StraitEdge2 is not much faster than the Lagoon, when paddled by a solo paddler, even if it is longer. But the Expedition is faster than the Lagoon, because it has more glide and allows me to use a longer, stronger stroke.
The bottom line is, when choosing a kayak model, remember that it's going to be YOU in the kayak. The fastest hardshell kayak I ever tried costs $7000 -- more than I'm willing to spend. It's also too heavy for me to lift onto a car roof by myself. The Expedition is way better for me! I found that as my fitness increased and I became familiar with each of my kayaks, I was able to paddle not only faster, but for longer outings and with less fatigue. That really mattered to me. What are the things that matter to you about kayaking?

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